/**  
 * All rights Reserved, Designed By <a href="www.itttq.com" target="_blank">www.itttq.com</a>
 * @date:   2017年9月17日 下午12:47:24
 * @Copyright: 2017 <a href="www.itttq.com" target="_blank">www.itttq.com</a> Inc. All rights reserved. 
 */  
package com.itttq.kb.utils;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Arrays;
import java.util.Random;

import javax.imageio.ImageIO;

/**   
 * @ClassName:  VerifyCodeUtil
 * @author: 迷蝶
 * @date:   2017年9月17日 下午12:47:24 
 * @Description: TODO
 *     
 * @Copyright: 2017 <a href="www.itttq.com" target="_blank">www.itttq.com</a> Inc. All rights reserved. 
 */
public class VerifyCodeUtil {
    
   //使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，去掉了1,0,i,o几个容易混淆的字符
   public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
   private static Random random = new Random();


   /**
    * 使用系统默认字符源生成验证码
    * @param verifySize    验证码长度
    * @return
    */
   public static String generateVerifyCode(int verifySize){
       return generateVerifyCode(verifySize, VERIFY_CODES);
   }
   /**
    * 使用指定源生成验证码
    * @param verifySize    验证码长度
    * @param sources   验证码字符源
    * @return
    */
   public static String generateVerifyCode(int verifySize, String sources){
       if(sources == null || sources.length() == 0){
           sources = VERIFY_CODES;
       }
       int codesLen = sources.length();
       Random rand = new Random(System.currentTimeMillis());
       StringBuilder verifyCode = new StringBuilder(verifySize);
       for(int i = 0; i < verifySize; i++){
           verifyCode.append(sources.charAt(rand.nextInt(codesLen-1)));
       }
       return verifyCode.toString();
   }
    
   /**
    * 生成随机验证码文件,并返回验证码值
    * @param w
    * @param h
    * @param outputFile
    * @param verifySize
    * @return
    * @throws IOException
    */
   public static String outputVerifyImage(int w, int h, File outputFile, int verifySize) throws IOException{
       String verifyCode = generateVerifyCode(verifySize);
       outputImage(w, h, outputFile, verifyCode);
       return verifyCode;
   }
    
   /**
    * 输出随机验证码图片流,并返回验证码值
    * @param w
    * @param h
    * @param os
    * @param verifySize
    * @return
    * @throws IOException
    */
   public static String outputVerifyImage(int w, int h, OutputStream os, int verifySize) throws IOException{
       String verifyCode = generateVerifyCode(verifySize);
       outputImage(w, h, os, verifyCode);
       return verifyCode;
   }
    
   /**
    * 生成指定验证码图像文件
    * @param w
    * @param h
    * @param outputFile
    * @param code
    * @throws IOException
    */
   public static void outputImage(int w, int h, File outputFile, String code) throws IOException{
       if(outputFile == null){
           return;
       }
       File dir = outputFile.getParentFile();
       if(!dir.exists()){
           dir.mkdirs();
       }
       try{
           outputFile.createNewFile();
           FileOutputStream fos = new FileOutputStream(outputFile);
           outputImage(w, h, fos, code);
           fos.close();
       } catch(IOException e){
           throw e;
       }
   }
    
   /**
    * 输出指定验证码图片流
    * @param w
    * @param h
    * @param os
    * @param code
    * @throws IOException
    */
   public static void outputImage(int w, int h, OutputStream os, String code) throws IOException{
       int verifySize = code.length();
       BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
       Random rand = new Random();
       Graphics2D g2 = image.createGraphics();
       g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
       Color[] colors = new Color[5];
       Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,
               Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE,
               Color.PINK, Color.YELLOW };
       float[] fractions = new float[colors.length];
       for(int i = 0; i < colors.length; i++){
           colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
           fractions[i] = rand.nextFloat();
       }
       Arrays.sort(fractions);
        
       g2.setColor(Color.GRAY);// 设置边框色
       g2.fillRect(0, 0, w, h);
        
       Color c = getRandColor(200, 250);
       g2.setColor(c);// 设置背景色
       g2.fillRect(0, 2, w, h-4);
        
       //绘制干扰线
       Random random = new Random();
       g2.setColor(getRandColor(160, 200));// 设置线条的颜色
       for (int i = 0; i < 20; i++) {
           int x = random.nextInt(w - 1);
           int y = random.nextInt(h - 1);
           int xl = random.nextInt(6) + 1;
           int yl = random.nextInt(12) + 1;
           g2.drawLine(x, y, x + xl + 40, y + yl + 20);
       }
        
       // 添加噪点
       float yawpRate = 0.05f;// 噪声率
       int area = (int) (yawpRate * w * h);
       for (int i = 0; i < area; i++) {
           int x = random.nextInt(w);
           int y = random.nextInt(h);
           int rgb = getRandomIntColor();
           image.setRGB(x, y, rgb);
       }
        
       shear(g2, w, h, c);// 使图片扭曲

       g2.setColor(getRandColor(100, 160));
       int fontSize = h-4;
       Font font = new Font("Algerian", Font.ITALIC, fontSize);
       g2.setFont(font);
       char[] chars = code.toCharArray();
       for(int i = 0; i < verifySize; i++){
           AffineTransform affine = new AffineTransform();
           affine.setToRotation(Math.PI / 4 * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2, h/2);
           g2.setTransform(affine);
           g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5, h/2 + fontSize/2 - 5);
       }
        
       g2.dispose();
       ImageIO.write(image, "jpg", os);
   }
    
   private static Color getRandColor(int fc, int bc) {
       if (fc > 255)
           fc = 255;
       if (bc > 255)
           bc = 255;
       int r = fc + random.nextInt(bc - fc);
       int g = fc + random.nextInt(bc - fc);
       int b = fc + random.nextInt(bc - fc);
       return new Color(r, g, b);
   }
    
   private static int getRandomIntColor() {
       int[] rgb = getRandomRgb();
       int color = 0;
       for (int c : rgb) {
           color = color << 8;
           color = color | c;
       }
       return color;
   }
    
   private static int[] getRandomRgb() {
       int[] rgb = new int[3];
       for (int i = 0; i < 3; i++) {
           rgb[i] = random.nextInt(255);
       }
       return rgb;
   }

   private static void shear(Graphics g, int w1, int h1, Color color) {
       shearX(g, w1, h1, color);
       shearY(g, w1, h1, color);
   }
    
   private static void shearX(Graphics g, int w1, int h1, Color color) {

       int period = random.nextInt(2);

       boolean borderGap = true;
       int frames = 1;
       int phase = random.nextInt(2);

       for (int i = 0; i < h1; i++) {
           double d = (double) (period >> 1)
                   * Math.sin((double) i / (double) period
                           + (6.2831853071795862D * (double) phase)
                           / (double) frames);
           g.copyArea(0, i, w1, 1, (int) d, 0);
           if (borderGap) {
               g.setColor(color);
               g.drawLine((int) d, i, 0, i);
               g.drawLine((int) d + w1, i, w1, i);
           }
       }

   }

   private static void shearY(Graphics g, int w1, int h1, Color color) {

       int period = random.nextInt(40) + 10; // 50;

       boolean borderGap = true;
       int frames = 20;
       int phase = 7;
       for (int i = 0; i < w1; i++) {
           double d = (double) (period >> 1)
                   * Math.sin((double) i / (double) period
                           + (6.2831853071795862D * (double) phase)
                           / (double) frames);
           g.copyArea(i, 0, 1, h1, 0, (int) d);
           if (borderGap) {
               g.setColor(color);
               g.drawLine(i, (int) d, i, 0);
               g.drawLine(i, (int) d + h1, i, h1);
           }

       }

   }
   public static void main(String[] args) throws IOException{
       File dir = new File("d:/ verifies");
       int w = 200, h = 80;
       for(int i = 0; i < 50; i++){
           String verifyCode = generateVerifyCode(4);
           File file = new File(dir, verifyCode + ".jpg");
           outputImage(w, h, file, verifyCode);
       }
   }
}